To AC or not to AC?
Hi, this is Hendrik from the app team. I mostly work on Datawrapper's internals, maintaining and improving our infrastructure. A fair amount of my time also goes into keeping our locator maps up to date, trying to balance improvements so that nothing changes too much when you republish a map. I’m used to looking at raw data before any visualization can happen.
In Germany, cooling in private buildings through anything but simple fans is still rare, and it’s not uncommon to be called a “weakling” when asking for something more efficient. Living directly under a dark, flat rooftop for about 15 years, I decided for myself that I want to step out as one of those weaklings.
My options to do so were quite limited, because I don’t have a balcony and can’t install a proper air conditioning unit outside the windows or on the rooftop. Earlier this year, I happened to see cheap monoblock air conditioners — those standalone units that use a hose placed in an open window to move hot air out — at a market and decided to try one out.
Unlike full ACs, where the heat energy from the refrigerant can be dispersed through an outside condenser, a monoblock separates air taken from the room into two flows: one of them is cooled down, passing the heat to the second flow, which needs to be transported out of the room as efficiently as possible.
This is also the main weakness of these systems. The air moved outside has to be replaced to balance the inside and outside pressure, so one can only choose between having air coming from the outside or from another room.
On hot days, when we want to use the AC most desperately, the air coming in can be so hot that it cancels out a monoblock’s capability to cool the primary airflow, no matter how well one prevents the hot air going out from coming directly back in. Still, there is one use case where a monoblock makes sense.
After a series of long sunny days, my attic apartment stays hot long after the outside temperature has fallen to an acceptable level. The walls and furniture are heated up and continue to keep the inside temperature high. In this situation, using a monoblock air conditioner can help cool the room down.
Above is a series of hot days where the heat continued to build up every night, even with the air conditioner switched on. Unfortunately, I don't have sample data without the AC, but if we look closer, its effect can be seen in the details.
When installed correctly, the effect that makes a monoblock almost useless during hot days is reversed once outside temperatures drop below the inside. The air that got heated up and pumped out by the machine now gets replaced by outside air that is cooler than the temperature in the room. Both the cold air coming in from the outside and the chilling effect of the machine add up and can cool a room notably at night.
The above example is from one of the hottest days of the year, when temperatures climbed as high as 38°C. Everything got so heated up that the outside temperatures dropping in the evening hardly had an effect on the inside.
I had a day off that day, so I could afford to wait until temperatures dropped low enough to comfortably sleep. While it’s hard to pinpoint how much faster the room cooled down with the AC switched on, what really catches the eye is what happened when I finally switched the noisy machine off at about 3 a.m.
The temperature bounced back a couple of degrees and continued to stay high, although it was much cooler outside at that time.
My key take-away from this analysis is that getting a monoblock air conditioner made sense for me. Even though it can’t do much more than provide a chilled stream during the day (at the expense that it slurps more warm air in), it effectively helps me cool the room down for sleep and also lowers the starting point for the next day's heat-up, so there is less build-up during a prolonged series of hot days.
That’s it for today. Thanks for reading. I hope it might help some of you with your own considerations about getting an AC. Stay with us for next week’s chart from Guillermina.
